Bone staple, instrument and method of use and manufacturing

Abstract

A new shape changing staple and instrument for the fixation of structures to include bone tissue and industrial materials. This new staple stores elastic mechanical energy to exert force on fixated structures to enhance their security and in bone affect its healing response. This staple once placed changes shape in response to geometric changes in the materials structure, including healing bone tissue. The staple is advanced over prior staples due to its: 1) method of operation, 2) high strength, 3) method of insertion, 4) compressive force temperature independence, 5) energy storing staple retention and delivery system, 6) compatibility with reusable or single use product configuration, 7) efficient and cost effective manufacturing methods, and 8) reduction in the steps required to place the device. In addition to the staple's industrial application an embodiment for use in the fixation of the musculoskeletal system is shown with staple, cartridge, and extrusion handle.

What is claimed is: 
     
       1. A pre-sterilized kit comprising
 (a) a staple device that comprises
 (i) only one staple, wherein the staple is a bone staple that comprises
 (A) a staple bridge, wherein
 (I) the staple bridge comprises a shape memory metal in a first shape, wherein the first shape is an elongated shape of the staple bridge and the staple bridge is restrained in the first shape by a cartridge, 
 (II) the staple bridge has a bridge shape such that when released from the cartridge, the bridge can move between the first shape and a second shape with no substantial plastic deformation of the staple bridge, wherein the second shape is a contracted shape of the staple bridge, 
 (III) at least a portion of the shape memory metal has a crystalline structure in the form of martensite; and 
 
 (B) a plurality of staple legs connected to the staple bridge, wherein
 (I) the plurality of staple legs comprise the shape memory metal, 
 (II) the staple is operable for moving when released from the cartridge between a parallel shape and a non-parallel shape without substantial plastic deformation of the staple, wherein the non-parallel shape is a convergent shape, 
 (III) the staple is in the parallel shape when the staple bridge is in the first shape and the staple legs are parallel, 
 (IV) the staple is in the non-parallel shape when the staple bridge is in the second shape and the staple legs are not parallel and are convergent, and 
 (V) the staple is operable for moving when the staple bridge and the plurality of staple legs are released from the cartridge to the non-parallel shape due to a transition of the crystalline structure of the shape memory metal from the martensite form to an austenite form without a change in temperature of the staple, and 
 
 
 (ii) the cartridge having a channel in which the staple bridge is restrained in the first shape and in which the staple legs are restrained in the parallel shape, wherein the cartridge has a retention tab that locks the staple bridge in the channel restrained in the first shape and locks the staple legs in the channel restrained in the parallel shape, 
 
 (b) an extrusion instrument that is configured to be movably coupled to the cartridge, wherein the extrusion instrument is operable for moving relative to the cartridge to extrude and release the staple from the cartridge while the extrusion instrument simultaneously disengages the retention tab, 
 (c) a drill bit; and 
 (d) a drill guide, wherein the staple, cartridge, extrusion instrument, drill bit, and drill guide are sterile. 
 
     
     
       2. The pre-sterilized kit of  claim 1 , wherein the staple-bridge has an S-shaped staple bridge shape. 
     
     
       3. The pre-sterilized kit of  claim 1 , wherein the staple-bridge has an O-shaped staple bridge shape. 
     
     
       4. The pre-sterilized kit of  claim 1 , wherein the shape memory metal comprises nitinol. 
     
     
       5. The pre-sterilized kit of  claim 1 , wherein the shape memory material can withstand a strain up to 6% with no substantial plastic deformation. 
     
     
       6. The pre-sterilized kit of  claim 1 , wherein the shape memory material can withstand a strain up to 8% with no substantial plastic deformation. 
     
     
       7. The pre-sterilized kit of  claim 1 , wherein the shape memory material can withstand a strain up to 13% with no substantial plastic deformation. 
     
     
       8. The pre-sterilized kit of  claim 1 , wherein the shape memory material can withstand a strain up to between 6% and 13% with no substantial plastic deformation. 
     
     
       9. The pre-sterilized kit of  claim 1 , wherein the staple bridge can withstand a strain up to 30% with no substantial plastic deformation. 
     
     
       10. The pre-sterilized kit of  claim 1 , wherein the pre-sterilized kit further comprises at least one ancillary instrument selected from the group consisting of mallets, forceps, and impactors. 
     
     
       11. A pre-sterilized kit of  claim 1 , wherein the pre-sterilized kit comprises a plurality of the staple devices.